Many existing portable electronic devices use voice or touch input as a method for the user to communicate commands to the devices or to control the devices. One example is a voice command system, which can map specific verbal commands to operations, for example, to initiate dialing of a telephone number by speaking the person's name. Another example is a touch input system, where the user can choose a specific device setting, such as adjusting the volume of the speakers, by touching a series of virtual buttons or performing a touch gesture. While voice and touch input can be an effective way to control a device, there may be situations where the user's ability to speak the verbal command or perform the touch gesture may be limited.